Method for producing a connecting part, connecting part produced in accordance with the method, tool for producing such a connecting part and fastening system having such a connecting part

ABSTRACT

The invention relates to a method for producing a connecting part ( 3 ) using an injection moulding method, wherein in a first step a closure part ( 11 ) forming a component of an adhesive closure is produced having adhesive or hooking elements and is introduced as an insert part into an injection mould in which in a second step by means of a back-injection process forms the connecting part ( 3 ) in the form of a structural part which contains the closure part ( 11 ) as an integral component.

The invention relates to a method for producing a connecting part using an injection molding process, preferably using a thermoplastic synthetic material. Specifically, the invention relates to the production of a connecting part, which has a fastening part having adhesive and/or hooking elements on one side, said fastening part forming a component of a contact fastener, wherein the connecting part may be part of a fastening system, in which system attachment parts are provided in order to form a contact fastener connection to a component that is to be connected, said attachment parts having adhesive and/or hooking elements, which can be releasably engaged with the corresponding adhesive and/or hooking elements of the respective connecting part. In addition, the invention relates to a tool for producing a connecting part of this kind.

Contact fastener connections are used in many areas in order to fasten objects or components such that they can be detached again. In motor vehicles, in order to prevent the mats from slipping or lifting up, said mats are frequently secured to the vehicle floor in such a way that connecting parts, which are anchored to the floor, and which have adhesive or hooking elements, are brought into adhesive contact or interlocking engagement with attachment parts, which are fastened to the floor mats, and which have corresponding adhesive or hooking elements. With reference to this, in the prior art, the connecting parts are designed having a disk-shaped base body, which can be anchored to the vehicle floor, on the upper side of which base body a contact fastening part having adhesive or hooking elements is attached. This is done by means of chemical or thermal adhesive bonds, for example using adhesives or hot glues that contain solvents. Apart from the environmental impact associated with solvent-containing substances, neither the chemical, nor the thermal adhesive bonds are satisfactory. As has been shown, when used in floor mats in motor vehicles, there is a risk that the contact fastening part and the base body will become detached from one another when the temperature and/or the relative humidity in the vehicle is too high. There is also a risk of detachment when the floor mat has been used for an extended period of time. This constitutes a safety risk, in particular when the floor mat on the driver's side slides forward towards the pedals while driving, which can lead to uncertainty on the part of the driver and may possibly result in an accident.

In order to avoid the risk that the contact fastening part may become detached from the base body, a solution disclosed in DE 10 2009 054 896 A1 is also prior art, according to which, the connecting part is produced in such a way that the base body and hooks are simultaneously formed as contact fastening elements in a single process step in an injection mold. Although in this procedure, there is practically no risk of detachment, the number of hooks that can be formed in the injection mold in which the base body is molded is nevertheless extremely limited, for example to a number not exceeding 50 hooks per cm². Such a limited achievable packing density of the hooking elements is not satisfactory.

Starting from this prior art, the object of the invention is to provide a method, which makes it possible to produce a connecting part having a contact fastener part, which can be reliably detachably connected to the base body, and at the same time, which is characterized by adhesive or hooking elements having a high degree of packing density.

This object is achieved according to the invention by a method having the features of claim 1 in its entirety.

Accordingly, an essential feature of the invention is that, in a first step, a fastening part having adhesive and/or hooking elements, said fastening part constituting a component of a contact fastener, is produced, at least in part, from at least one synthetic material, and is introduced as an insertion part into an injection mold, in which, in a second step, at least one additional synthetic material is introduced into the injection mold by means of a back injection process at a predefinable pressure and at a predefinable temperature to form a base body, said synthetic material being introduced in such a way that the respective additional synthetic material, at least in part, forms a common molten mass with the at least one synthetic material of the fastening part, after the cooling of which, the fastening part, together with the base body firmly bonded thereto, form the connecting part as an integrated composite component. This opens up the possibility of using a fastening part as an insertion part, which is produced in a separate production process, which is oriented towards fastening parts of modern contact fasteners, in which adhesive or hooking elements of various kinds are provided, thus in addition to hooks, loops or mushroom-shaped elements having round or flat heads as well, as they can be produced having a very high degree of packing density using the special method provided therefore. Because in a second step, in which an insertion part is introduced into the injection mold by means of a back injection process, the connecting part is formed in a separate step, in which the insertion part is back injected, the connecting part is made an integral component with the fastening part, from which said connecting part cannot be detached, by means of a firmly bonded connection created during the back injection process.

The fastening part that forms the insertion part is preferably produced from a synthetic material having a planar support part, on one side of which, the adhesive or hooking elements, which are integrally formed with the support part, project.

In addition, it is preferably provided that the support part is kept free of anchoring elements, such as mushroom-shaped, hook-shaped or loop-shaped elements on the side of said support part facing the base body, in order to produce an evenly extending, planar fused joint across larger areas between the synthetic materials of the fastening part and base body in the injection mold.

In a particularly advantageous manner, an insertion part may be used, the adhesive or hooking elements of which are formed by means of a mold from the thermoplastic synthetic material of the support part, for example from polyamide 6, polyamide 6.6, polyamide 12.

An insertion part may also be used with a support part, which comprises a single-thread knitted fabric made of a synthetic material, such as polyamide 6, polyamide 6.6, polyphenylsulfone, wherein adhesive or hooking elements are formed from filaments of the single-thread knitted fabric.

In addition, an insertion part may also be used with a support part, which comprises a multi-thread knitted fabric made of synthetic material such as polyamide 6, polyphenylsulfone, polypropylene, wherein adhesive or hooking elements are formed from filaments of the multi-thread knitted fabric.

In a particularly advantageous manner, a polyamide or polypropylene, preferably having glass fiber reinforcement, may be used as a synthetic material for the back injection process.

The same synthetic material may also be used for the back injection process as was used for the production of the insertion part as well. In the production of a good bonded connection, it is advantageous when the connection partners have the same or at least similar softening and melting temperatures.

In a particularly advantageous manner, the side of the support part of the insertion part that is free of adhesive or hooking elements may be provided with a coating of polyurethane, which acts as a reaction mediator during the back injection process, prior to the introduction of said insertion part into the injection mold. An additive of this kind facilitates the formation of a firmly bonded connection during back injection. When producing the connection, a solvent-free, moisture-curing hot-melt adhesive based on reactive polyurethane prepolymers may also serve as a reaction mediator or adhesive, said hot-melt adhesive containing at least one polyester polyol in a concentration between 10% and 90%, possibly polyether polyol in a concentration between 0% through 50%, as well as at least polydisocyanate in a concentration by weight between 5% and 35%.

The back injection process provided for in the invention is a technique such as that described on page 118 of the technical publication “Spritzgieβwerkzeuge kompakt” [Understanding Injection Molds] by Harry Pruner and Wolfgang Nesch, for example, based on an example, in which a decorative material is permanently bonded with a part made of synthetic material, wherein the firmly bonded connection is formed by the introduction of a thermoplastic molten mass into the decorative material.

According to claim 9, the subject matter of the invention is also a connecting part produced by means of the method according to one of the claims 1 through 8, which connecting part having a base body, preferably in the form of a flat disk, which has a fastening part having adhesive or hooking elements on one side, and which preferably has an anchoring or other fixing device for affixing the disk to a structure on the side that is free of the adhesive or hooking element. The base body may also comprise another support part, in particular in the form of a disk, or may be a component of a structurally larger system, for example in the form of automotive parts, such as chassis components. A layer of adhesive or an additional adhesive or fastening part may also serve as a fixing device, as is used on the upper side of the base body.

In a preferred embodiment, the disk is round, wherein the anchoring device has an anchoring stud, which projects from the central region of the base body as an integral part thereof, said anchoring stud being provided for the retaining engagement in an opening of the structure.

At least one laterally projecting retaining element may be provided on the anchoring stud, wherein retaining elements in the form of catches, which project laterally diametric to one another, or spiral ridges, which form an outer thread, may preferably be provided.

According to claim 13, the subject matter of the invention is also a tool for producing a connecting part according to one of the claims 9 through 12 by means of the method according to one of the claims 1 through 8, wherein the tool has an injection mold, which has a first tool part having a first mold cavity for a back injection process, said mold cavity forming at least a large part of the base body, as well as a second tool part, which closes the first mold cavity in a back injection process, thereby forming a second mold cavity, into which second cavity the insertion part, which forms the fastening part, can be introduced.

The second mold cavity preferably has a device for positioning and retaining the insertion part that has been introduced.

As such, the arrangement may be especially advantageously made such that the second mold cavity has a contact surface, on which the insertion part can be placed with the side having the adhesive or hooking elements, wherein the device for positioning and retaining has a mold part in the central region, which projects out of the contact surface, which mold part engages in a recess in the insertion part, which is designed for said mold part, and as a result, the insertion part is secured in an aligned position.

This mold part may have the form of a rectangular ridge, the contour of which is adapted to the recess of the insertion part, said ridge having a projection in the form of a protuberance, which forms a depression in the base body during the back injection process. A depression formed in this way can facilitate the attachment of the connecting part to a structure by turning the connecting part through the intervention of a turning tool.

In particularly advantageous exemplary embodiments, it is provided that the entire contact surface of the second mold cavity is provided with micro-contouring having a pattern of fine depressions and projections. In adapting to the microstructure of the adhesive or hooking elements, structuring of this kind facilitates the contact of the said elements with the wall of the mold.

According to claim 18, the subject matter of the invention is also a fastening system for affixing a component by means of at least one connecting part produced by means of the method according to claims 1 through 8, wherein each connecting part is allocated to an attachment part that is connected to the component having adhesive or hooking elements, which can be releasably engaged with the corresponding adhesive or hooking elements of the connecting part.

The respective attachment parts may be designed such that they are also disk-shaped, and thus adapted to the form of the connecting parts.

In a particularly advantageous manner, in order to secure the position of a floor mat of a motor vehicle, the respective connecting parts can be anchored to the floor of the motor vehicle and the attachment parts can be attached to the floor mat.

The invention is explained in greater detail below on the basis of the drawings. Shown are:

FIG. 1 an oblique view in perspective of a partial section of the floor of a motor vehicle, and a mat, which is partially attached to the floor, said mat being provided with a fastening system having connecting parts according to the invention;

FIG. 2 a top view of an exemplary embodiment of a connecting part according to the invention;

FIG. 3 a sectional view corresponding to the section line III-III of FIG. 2;

FIG. 4 a greatly enlarged oblique view in perspective of a partial section of the exemplary embodiment of the connecting part having the same sectional plane as that shown in FIG. 3;

FIG. 5 an enlarged detail of the area designated as V in FIG. 3, wherein hooking elements of the associated fastening part have been greatly schematically simplified and are not depicted to scale;

FIGS. 6 to 8 the partial sections corresponding to FIG. 5, each having different adhesive or hooking elements of the fastening part;

FIG. 9 an oblique view in perspective of a first tool part of an injection mold for producing a connecting part according to the invention;

FIG. 10 an oblique view in perspective of the second tool part of the injection mold;

FIG. 10a an enlarged depiction of the region designated as X in FIG. 10;

FIG. 11 a front view of two mold parts of the first tool part positioned such that said parts have been moved apart from one another, depicted in a larger scale as compared to FIG. 9;

FIG. 12 a side view of one of the mold parts from FIG. 11, as viewed from the side facing the other mold parts;

FIG. 13a-13c sketched depictions of the work steps for producing a micro-contour on a mold wall of the second tool part of the injection mold;

FIG. 14 a microscopically enlarged detail as a schematic view in perspective, which depicts the micro-contour in a partially completed state;

FIG. 15 an enlarged oblique view in perspective of the connecting part according to the exemplary embodiment from FIG. 4, as viewed top down;

FIG. 16 an enlarged oblique view in perspective of an exemplary embodiment of the connecting part having a fastening part with hooks;

FIG. 17 a further enlarged, broken sectional view of the exemplary embodiment from FIG. 16, and

FIG. 18 an oblique view in perspective similar to that in FIG. 16 with a fastening part having adhesive elements, which have planar surface parts on the upper side thereof.

The invention is explained in greater detail below on the basis of an example of the production of a connecting part, which is part of a fastening system for affixing a floor mat to the floor of a motor vehicle. It is understood that the connecting parts according to the invention may be used advantageously in other areas of application, in which contact fasteners are used, whether this be in the industrial, sporting or leisure sectors and the like. FIG. 1 shows a schematic partial area of the floor of a motor vehicle 1 having a connecting part in the form of a connection disk 3 corresponding to an exemplary embodiment of the invention anchored thereon. In addition, FIG. 1 shows a part of the floor mat 5 in a position prior to being placed on the floor 1. In the case of the floor mat 5, in the example shown, said mat is a rubber mat, which can be placed on the floor 1 as an accessory part. Likewise, this may be a mat, which may form a standard part of the vehicle, for example in the form of a textile mat. Attachment parts 7 are provided on the floor mat 5 as components of a contact fastener, which attachment parts, like the disks 3 on the floor of the vehicle 1, have a circular contour and adhesive and hooking elements, for example a fleece material, in order to form a contact fastener connection with the disks 3. In FIG. 1, only one pair consisting of disk 3 and attachment part 7 from among the number of pairs in question can be seen.

FIG. 2 shows an exemplary embodiment, approximately twice the size of a practical embodiment, of the connecting part in the form of the disk 3 having a round base body 9, which includes a fastening part 11 having adhesive or hooking elements on the upper side of said base body shown in FIG. 2, said elements merely being indicated in a schematic manner in FIG. 2, and likewise in the sectional view in FIG. 3. An anchoring stud 13 is integrally formed on the base body 9, in the central region on the underside thereof facing away from the fastening part 11, at the free end of which stud, anchoring catches 15, which project laterally diametric to one another, are formed; see also FIG. 4. As is shown most clearly in FIGS. 2 and 4, a recessed depression 17 is molded in the upper side, centrally located in the base body 9. This depression facilitates the rotation of the disk 3 when said disk is anchored to the floor 1, wherein the stud 13 is inserted through a slot opening of the floor 1 and then turned. The fastening part 11 is prefabricated as an insertion part for the molding process, for example by punching out round sections from the length of a contact fastener material. Because the fastening part is introduced as an insertion part into an injection mold and the injection process is carried out using a back injection technique when the base body 9 is shaped, in the finished state shown in FIGS. 2 through 4, the fastening part 11 forms a single-piece, integral component of the disk 3. As is shown particularly clearly in FIGS. 2 and 4, the base body 9 comprises a disk-shaped base plate 10, the outer circumference of which transitions into a raised outer edge 12. In a practical embodiment, the base plate 10 has a diameter of 60 mm. In the embodiment according to FIG. 4, the height of the outer edge 12 is greater than the height of the individual adhesive or hooking elements of the fastening part 11 joining the base of the disk. In this way, the adhesive or hooking elements can be protected against damage both from above, and from the side and, as viewed from the front side of the disk 3, are fully accessible to mesh or engage with a corresponding fastening material, for example in the form of loop material, which is located on the respective attachment 7 part on the floor mat 5.

In a highly schematically simplified and enlarged view of the area designated as V in FIG. 3, FIGS. 5 through 8 illustrate a plurality of variants of the design of the fastening part 11 having different kinds of hooking elements 21 (FIGS. 5 through 7) or adhesive elements 23 (FIG. 8) located on a support part 19. Thus, FIG. 8 shows adhesive elements 23, which make an adhesion attachment on smooth opposing surfaces possible through planar surfaces 25 on the widened head parts opposite the stems by means of van der Waals forces, but also a locking action with corresponding elements of the same kind or having the shape of a mushroom head. When using adhesive elements 23 having an adhesion behavior, however, it is advantageous that the projecting, planar head surfaces 25 of such adhesive elements 23 be allowed to project above the outer edge 12 of the disk by a predeterminable distance such that said head surfaces can be locked in place by a corresponding film material, which may be a component of the floor-foot mat 5, which is to be placed on the disk 3. FIGS. 5 through 7 depict hooks 18 or, respectively, loops 20 or, respectively, mushroom heads 22 for interlocking engagement with the corresponding elements. The hooking elements 21 can be produced on a support part 19 in the form of a synthetic woven fabric or synthetic knitted fabric using a method known from the prior art, as can be found, inter alia, in DE 10 2008 007 913 A1, said fabric having projecting filaments, for example in the form of pile threads of a single-thread knitted fabric. The hooks 18 shown in FIG. 5 can be created by severing the loops 20, as they are provided as hooking elements 21 in FIG. 6. Mushroom heads 22, as they are shown in FIG. 7, can be obtained when pile threads, each of which has been severed at the upper arch thereof, are heated in such a way that said threads are deformed to produce mushroom heads. Adhesive elements 23, whereby the planar surfaces thereof make an adhesive connection possible, however whereby the heads thereof, which are wider than the stems thereof, make hooking possible, can be produced using the forming method such as that described in DE 198 28 856 C1, wherein synthetic materials such as polyamide 6, polyamide 6.6, polyamide 12, inter alia, may be advantageously used. Polyamide 6, polyamide 6.6, polyphenylsulfone, inter alia, in the form of a synthetic woven fabric may be advantageously considered for support parts 19. Polyamide 6, polyphenylsulfone, and polypropylene are especially suitable for support parts in the form of a synthetic knitted fabric.

FIGS. 9 through 12 show essential components of an injection mold for producing the disk 3 provided as a connecting part using the back injection method, wherein the base body 9 is formed from a thermoplastic synthetic material, such as polyamide or polypropylene, preferably having glass fiber reinforcement. FIGS. 9 and 10 show a first tool part 27 or, respectively, a second tool part 29, which can be placed against one another in order to seal the mold cavities formed therein. Of these, a first mold cavity 31 is provided in the first tool part 27, and a second mold cavity 33 is provided in the second tool part 29. The first mold cavity 31 is delimited by movable, identically designed mold parts 35, which are movable, and which are depicted in FIG. 11 in a position in which said mold parts have been moved apart from one another. In the closed position shown in FIG. 9, the mold parts 35 each form a mold half for forming the round disk shape of the base body 9. Of the hot runners for supplying the injection material, only one runner 37 is visible in FIG. 12, which runner opens into the mold depression 39 of the mold part 35 shown, which forms the catch 15 on the anchoring stud 13. The height of the edge 41 that delimits the first mold cavity 31 is selected in such a way that, in conjunction with the second mold cavity 33 of the second tool part 29, the desired thickness of the base body 9 above the anchoring stud 13, i.e., the desired thickness of the disk 3, is formed.

The prefabricated insertion part comprising the support part 19 with fastening part 11 can be inserted into the second mold cavity 33 formed in the second tool part 29 for the injection process. This mold cavity has a recessed, planar contact surface 45, which is enclosed by an edge 43, on which surface the fastening part 11 can be placed with the side having the adhesive or hooking elements 23, 21. In order to secure the insertion part thus placed in an aligned position before closing the injection mold, a ridge 47 is provided in the central region of the contact surface 45, which ridge projects from the plane thereof. This ridge has the form of a rectangular block having a contour, which is adapted to the size of a recess 49 formed in the support part 19 in such a way that the insertion part is secured by a fitted engagement of the ridge 47. A projecting, curved protuberance 51 extends in the longitudinal direction of the ridge 47 in the central region thereof, which protuberance forms the depression 17 in the base body 9 during the back injection process.

In conjunction with the region designated as X in FIG. 10, FIG. 10a shows a greatly enlarged view of a modified design of the surface of the contact surface 45 of the second mold cavity 33. In derogation from a completely smooth surface of the contact surface 45, in this variant, the surface is provided with micro-contouring 53, as a result of which, an optimal contact is provided for the adjoining adhesive or hooking elements 23, 21 of the fastening part 11 of the insertion part for the back injection process. The micro-contouring 53 may be formed by a pattern of fine grooves 57 and elevations 55; see FIG. 13. This Figure shows a sketch, which clarifies an advantageous method of producing the elevations 55 and grooves 57. As depicted in a) in FIG. 13, knurls can be used to form peaks 59 between the depressions 57. As b) in FIG. 13 shows, planar surface portions 61 can be formed between the grooves by grinding off the peaks 59. As c) in FIG. 13 shows, the planar surface parts 61 can be rounded by brushing in such a way that the rounded elevations 55 shown are created, which, in conjunction with the grooves 57, form an optimal micro-contour for the contact surface 45.

In FIG. 14, which shows a detail of the contour 53 in a state prior to full completion, of the peaks 59 formed by knurling and the surface parts 61 formed by grinding, not all are numbered. As shown, spaces are formed between the truncated cones delimited by the surfaces 61, which truncated cones will be rounded off to the free end thereof, in order to form the elevations 55 pursuant to FIG. 13c ). These spaces serve to receive the adhesive or hooking elements 23, 21 of the fastening part 11 of the insertion part, in order that said elements are not inadvertently pressed together in the mold during the back injection process. The disk 3, which is completed after the back injection process, and which serves as a connecting part, therefore makes it possible to securely affix the respective component that is to be secured, such as the floor mat 5.

FIG. 15 shows a part of the upper side of the disk 3 of an exemplary embodiment, in which hooking elements in the form of mushroom heads 22 are provided in accordance with FIG. 4. As is also clear from FIG. 4, the circumferential outer edge 12 has a projection that extends above the plane of the upper side of the mushroom heads 22. When mounting the component that is to be attached, such as the floor mat 5, wherein the mushroom heads 22 can be hooked with a fleece material on attachment parts 7 of the floor mat 5, the circumferential outer edge 12 forms a kind of sealing edge, which prevents dirt particles, which may appear on the floor area of a vehicle, from entering the fastener area unhindered. As can clearly be seen in the photomicrograph shown in FIG. 15, the mushroom heads 22 are designed in such a way that the diameter of the half-sphere-shaped head parts 24 (only some are numbered in FIG. 15) have approximately double the diameter of the round stems 26 (only some are numbered), wherein the stems 26 have approximately four times the length of the head parts 24.

Similarly in the manner of a photomicrograph, FIG. 16 depicts an exemplary embodiment of the disk 3, in which hooks 18 corresponding to those in FIG. 5 are provided as hooking elements. As in FIGS. 4 and 15, the circumferential outer edge 12 has a projection that extends beyond the plane of the upper side of the hook 18. As shown in the further enlarged depiction of this example in FIG. 17, the support part 19, on which the hooks 18 are located, is made an integral component of the plate 10 of the base body 9 through the back injection process. The same applies to the support part 19 having the mushroom heads 22 in the exemplary embodiment in FIGS. 4 and 15.

In a similar depiction, FIG. 18 shows an exemplary embodiment having adhesive elements 23, which do not have round mushroom heads 22 at the upper end thereof but instead, which have planar surface parts 25; see FIG. 8, in which adhesive elements 23 having this shape are depicted. Since these adhesive elements 23 may not only be considered for an interlocking engagement with correspondingly designed contact fastener elements, but may also form an adhesive connection (a so-called gecko-like connection) having smooth contact surfaces, in this exemplary embodiment, the outer edge 12 of the otherwise uniformly designed disk 3 is designed such that it does not project, or only slightly projects above the surface parts 25 of the adhesive elements 23. Otherwise, the design of the disk 3 corresponds to that of the other exemplary embodiments. Alternatively, the disk may be designed without the circumferential outer edge 12 projecting from the plane of the plate 10 of the base body 9, such that the insertion part extends with the support part 19 thereof to the outer circumference, or just short of the outer circumference of the plate 10. 

1. A method for producing a connecting part (3) using an injection molding process, wherein, in a first step, a fastening part (11) having adhesive and/or hooking elements (21, 23), said fastening part forming a component of a contact fastener, is produced, at least in part, from at least one synthetic material, and is introduced as an insertion part into an injection mold (27, 29), in which, in a second step, at least one additional synthetic material is introduced into the injection mold (27, 29) by means of a back injection process at a predefinable pressure and at a predefinable temperature to form a base body (9), said synthetic material being introduced in such a way that the respective additional synthetic material, at least in part, forms a common molten mass with the at least one synthetic material of the fastening part (11), after the cooling of which, the fastening part (11), together with the base body (9) firmly bonded thereto, form the connecting part (3) as an integrated composite component.
 2. The method according to claim 1, characterized in that the fastening part (11), which forms the insertion part, is produced from a synthetic material having a planar support part (19), on one side of which, the adhesive or hooking elements (21, 23), which are integrally formed with the support part (19), project.
 3. The method according to claim 2, characterized in that the support part (19) is kept free of anchoring elements such as mushroom-shaped, hook-shaped or loop-shaped elements on the side of said support part facing the base body (9), in order to produce an evenly extending, planar fused joint across larger areas between the synthetic materials of the fastening part (11) and base body (9) in the injection mold (27, 29).
 4. The method according to claim 1, characterized in that an insertion part (19, 11) is used, the adhesive or hooking elements (21, 23) of which are formed by means of a mold from the thermoplastic synthetic material of the support part (19), such as polyamide 6, polyamide 6.6, polyamide
 12. 5. The method according to claim 1, characterized in that an insertion part (11, 19) having a support part (19) is used, which support part comprises a single-thread knitted fabric made of a synthetic material, such as polyamide 6, polyamide 6.6, polyphenylsulfone, wherein hooking elements (21) are formed from filaments of the single-thread knitted fabric.
 6. The method according to claim 1, characterized in that an insertion part (11, 19) having a support part (19) is used, which support part comprises a multi-thread knitted fabric made of a synthetic material such as polyamide 6, polyphenylsulfone, polypropylene, wherein hooking elements (21) are formed from filaments of the multi-thread knitted fabric.
 7. The method according to claim 1, characterized in that polyamide or polypropylene, preferably having glass fiber reinforcement, is used for the back injection process as a respective additional synthetic material, said material having a melting temperature, which is preferably the same, or falls within the same range, as the respective synthetic material used for the fastening part (11).
 8. The method according to claim 1, characterized in that the same synthetic material is used for the back injection process as is used for the production of the insertion part (11, 19).
 9. The method according to claim 1, characterized in that the side of the support part (19) of the insertion part (11, 19) that is free of adhesive or hooking elements (21, 23) is provided with a coating of polyurethane, preferably a moisture-curing polyurethane, which acts as a reaction mediator during the back injection process, prior to the introduction of said insertion part into the injection mold (27, 29).
 10. A connecting part produced by means of the method according to claim 1 having a base body (9), preferably in the form of a flat disk (3), which has a fastening part (11) having adhesive and/or hooking elements (21, 23) on one side, said fastening part forming a component of a contact fastener, and which preferably has an anchoring or other fixing device (13, 15) for affixing the base body (9) to a structure (1) on the other side, and in which the respective synthetic materials of the fastening part (11) and base body (9) used are intrinsically bonded with one another along at least one planar extending connection surface.
 11. The connecting part according to claim 10, characterized in that the disk (3) is round, and the anchoring device (13, 15) has an anchoring stud (13), which projects from central region of the base body (9) as an integral part thereof, said anchoring stud being provided for the retaining engagement in an opening of the structure (1).
 12. The connecting part according to claim 11, characterized in that at least one laterally projecting retaining element (15) is provided on the anchoring stud (13).
 13. The connecting part according to claim 12, characterized in that retaining elements in the form of catches (15), which project laterally diametric to one another on the anchoring stud (13), or spiral ridges, which form an outer thread of the anchoring stud (13), may be provided.
 14. A tool for producing a connecting part by the method of claim 9, having an injection mold, which has a first tool part (27) having a first mold cavity (31) for a back injection process, said mold cavity forming at least a large part of the base body (9), as well as a second tool part (29), which closes the first mold cavity (31) in the back injection process, thereby forming a second mold cavity (33), into which second cavity the insertion part (11, 19) can be introduced, and in that both mold cavities (31, 33) are designed having the same, or substantially the same size.
 15. The tool according to claim 14, characterized in that the second mold cavity (33) has a device (47) for positioning and retaining the insertion part (11, 19) that has been introduced.
 16. The tool according to claim 14, characterized in that the second mold cavity (33) has a contact surface (45), on which the insertion part (11, 19) can be placed with the side having the adhesive or hooking elements (21, 23), and in that the device for positioning and retaining has a mold part (47) in the central region thereof, which projects from the contact surface, which mold part engages in a recess (49) in the insertion part (11, 19), which is designed for said mold part.
 17. The tool according to claim 14, characterized in that the projecting mold part has the form of a rectangular ridge (47), the contour of which is adapted to the recess (49) of the insertion part (11, 19), said ridge having a projection in the form of a protuberance (51), which forms a depression (17) in the base body (9) during the back injection process.
 18. The tool according to claim 14, characterized in that the entire contact surface (45) of the second mold cavity (33) is provided with micro-contouring (53) having a pattern of fine depressions (57) and projections (55).
 19. A fastening system for affixing a component (5) by means of at least one connecting part (3) produced by means of the method according to claim 1, wherein each connecting part (3) is allocated to an attachment part (7) that is connected to the component (5) having adhesive or hooking elements, which can be releasably engaged with the corresponding adhesive or hooking elements (21, 23) of the connecting part (³).
 20. The fastening system according to claim 19, characterized in that the respective attachment parts (7) are designed such that they are disk-shaped, thus adapted to the form of the connecting parts (3).
 21. The fastening system according to claim 19, characterized in that, in order to secure the position of a floor mat (5) of a motor vehicle, the respective connecting parts (3) can be anchored to the motor vehicle floor (1) and the attachment parts (7) can be attached to the floor mat (5). 